The fresh produce industry incorporates the use of stackable corrugated fiberboard cartons or returnable plastic crates of various sizes and shapes to accommodate a wide array of fresh fruits and vegetables for transportation to market. In general, there are two broad categories of stackable fiberboard cartons used in the produce industry, open style cartons which incorporate apertures such as hand-holds and concavities for refrigerated air circulation and closed style cartons which do not include the apertures and concavities but does incorporate selective gas permeable membranes to limit gas exchange between the sealed cartons and ambient atmosphere.
The main advantages of the open style cartons allows for direct field packing of the harvested produce in the cartons, followed by refrigeration and shipment to market. The simple packaging and cooling of the produce provides significant time, labor and cost savings. The main disadvantages of this type of packaging is that the free movement of oxygen around the produce reduces the amount of time the produce can be stored and/or transported. To offset some of these deleterious effects, produce is harvested earlier in the growing season, usually before optimal nutritional values and desirable tastes have developed, thus reducing the quality of the produce delivered to market. Another disadvantage of the open style packaging is the minimal protection afforded to temperature excursions occasionally encountered during transportation to market.
The lack of insulating air and packaging materials surrounding the produce allows temperature changes to more rapidly impact the stored produce. For temperature sensitive produce, (e.g., peaches) an extended refrigeration failure could result in the loss of an entire produce shipment. Examples of typical stackable containers include U.S. Pat. No. 5,121,877 to Bodary, et al. which discloses a palletized containers for ripening of fruit during shipment and storage; U.S. Pat. No. 3,871,570 to Garmon which discloses a stackable tray for shipping of fresh fruits and vegetables; U.S. Pat. No. 5,967,406 to Moorman which discloses a stackable Bliss style shipping container which can be reconfigured into a retail, club or wholesale market display container; U.S. Pat. No. 5,052,615 to Ott, et al. which discloses another stackable shipping and display carton; U.S. Pat. No. 4,101,048 to Rieben, et al. which discloses another stackable produce field carton; and U.S. Pat. No. 3,863,831 to Wozniacki, et al. which discloses a stackable shipping carton which allows ventilation and/or cooling of the contents of the carton.
Corrugated cartons which incorporate selective gas permeable membranes are known in the relevant art as modified atmosphere packaging (MAP). Modified atmosphere packaging is available in various shapes and sizes and generally includes lids or flaps that are integral to the carton. The major advantages of using MAP is that produce life is extended beyond non modified atmosphere packaging anywhere from 10 to 25 days depending on the particular produce being packaged and weight loss due to refrigeration is greatly reduced. The extended produce life allows the produce to be harvested closer to maturity thus retaining optimal nutritional values and desirable tastes and facilitates longer transportation durations, a particularly important consideration when fresh fruits and vegetables are being transported from tropical growing regions to markets located around the globe (e.g., bananas).
The product life extension capability of MAP is extremely important in the premium fresh produce industry where considerable cost savings over regular cartons may be obtained where such produce would have to be air shipped rather than using considerably less expensive shipping alternatives such as cargo vessels and/or land transportation. The sealed packaging also affords greater protection from temperature excursions due to the increased insulating properties of the modified atmosphere and enveloping carton surrounding the produce. The are however, several disadvantages to the relevant art modified atmosphere packaging including difficulties in efficiently re-refrigerating palletized or stacked produce during shipment due to the inability to provide adequate refrigerated air circulation around the palletized and/or stacked produce cartons, in particular interior cartons which are insulated from the refrigerated air by the surrounding exterior cartons.
Another disadvantage of the relevant art modified atmosphere packaging is that there is generally no way to visually inspect the produce inside after the cartons have been sealed. Damaged produce, insect pests and other problems may not be discovered until the produce is delivered to its final destination. Examples of packaging incorporating modified atmosphere technologies include U.S. Pat. No. 5,575,418 to Wu, et al. discloses a corrugated paperboard carton which includes a gas permeable membrane incorporated into the package for shipment of fresh produce and cut flowers; European patent application 0 282 180 to Greengrass discloses a container, bag or encasement which incorporates a gas permeable membrane for the delayed ripening of produce enveloped by the permeable membrane. U.S. Pat. No. 4,515,266 to Myers discloses a sealed container filled with a preservative gas for inhibiting bacterial growth; and U.S. Pat. No. 6,050,412 to Clough, et al. discloses a method and apparatus for packaging and shipping cut flowers using a modified atmosphere package.
None of the cited references provides stackable packages which incorporates modified atmosphere technology, allows cooling ventilation of stacked and/or palletized packages and facilitates visual inspection of the package contents without having to open the sealed package.
Therefore, what is needed is a corrugated package which incorporates modified atmosphere technology, allows field harvesting and packaging of produce in either the field or in a centralized facility, allows cooling ventilation of stacked and/or palletized packages directly in the modified atmosphere packaging, allows visual inspection of the packaged produce at any point following packaging and provides the ability to re-establish refrigeration of the produce during transit is highly desirable.